Table 1.
Characteristics of Participants at Entry into DCCT and at an average of 32 Years of Follow-up (n = 1,051) *
| Characteristic | Entry into DCCT (1983-1989) |
32 Years Follow-up (2019) |
|---|---|---|
| Intensive treatment assignment in DCCT (%) | 53 | 53 |
| Demographic characteristics | ||
| Age [median (range) years] | 27 (13-39) | 59 (43-75) |
| Female sex (%) | 47 | 47 |
| White race (%)† | 96 | 96 |
| Education (years) | 14 ± 3 | 16 ± 2 |
| Professional or technical occupation (%) | 32 | 55 |
| Verbal IQ‡ | 112 ± 11 | ND |
| Full-scale IQ‡ | 114 ± 10 | ND |
| Medical history | ||
| Duration of diabetes [median (range) years] | 4 (1-15) | 37 (30-51) |
| History of hypertension (%)§ | 3 | 68 |
| History of hyperlipidemia (%)§ | 22 | 76 |
| Current cigarette smoker (%) | 15 | 7 |
| Current occasional or regular alcohol use (%) | 22 | 50 |
| Medication ¶ | ||
| ACE inhibitors or ARB (%) | ND | 43 |
| Lipid-lowering medication (%) | ND | 71 |
| Physical examination | ||
| Body mass index (kg/m2) | 23·3 ± 2·8 | 29·3 ± 5·8 |
| Blood pressure (mm Hg) | ||
| Systolic | 114 ± 12 | 124 ± 15 |
| Diastolic | 72 ± 9 | 69 ± 9 |
| Laboratory values | ||
| Glycosylated hemoglobin A1c (%) | 8·7 ± 1·5 | 7·8 ± 1·2 |
| Plasma lipids (mg/dl)∥ | ||
| Total cholesterol | 175 ± 33 | 171 ± 36 |
| HDL cholesterol | 51 ± 12 | 64 ± 20 |
| LDL cholesterol | 109 ± 29 | 92 ± 30 |
| Triglycerides | 78 ± 41 | 74 ± 53 |
| Complications †† | ||
| eGFR <60 mL/min/1·73 m2 (yes vs. no) | 0 | 13 |
| PDR (yes vs. no) | 0 | 26 |
| Cardiovascular disease (yes vs. no) | 0 | 15 |
Data are means ± SD or percent unless otherwise noted. ND denotes no data, ACE angiotensin-converting enzyme, ARB angiotensin-receptor blocker, HDL high-density lipoprotein, LDL low-density lipoprotein, PDR proliferative diabetic retinopathy, and eGFR estimated glomerular filtration.
Race was self-assigned. “White” denotes white, non-Hispanic.
The normative mean IQ score is 100 ± 15.
Hypertension was defined by a systolic blood pressure of at least 140 mm Hg, a diastolic blood pressure of at least 90 mm Hg, documented hypertension, or the use of antihypertensive medications. Hyperlipidemia was defined by an LDL cholesterol level of at least 130 mg per deciliter or the use of lipid-lowering medications.
Medication history was not obtained during the DCCT, but the use of ACE inhibitors was discouraged, and statins were not widely available or in use during the DCCT.
To convert values for cholesterol to millimoles per liter, multiply by 0·02586. To convert values for triglycerides to millimoles per liter, multiply by 0·1129.
Any report between DCCT baseline and 32 years of follow-up.